Get some chlorine in there before your pool turns green! Each quart of 6% bleach will raise the cl by 1 to 1.5ppm in a 24ft AG pool. Test each evening, and add enough bleach to get back to 6ppm. Also add a half a box of Borax at a time (to the skimmer), wait a few hours to let it circulate, retest and redose til you get ph to 7.4-7.6. You can also add a half a box of baking soda in the same way until you get the alk to 80-125. Calcium hardness is irrelevent in a vinyl pool. If you find that you are having a hard time keeping chlorine in the pool through a day, you may decide later to bump the cya level up to 40 or 50, but try it at 30 for now.